Rock-drill



(No Model.) 0 I 2 Sheets-Sheet 1. W. EL ADAMS ROCK DRILL.

No. 425,532. Patented Apr. 15, 1890.

The mums Pins: 00.. mommmz, msmum'cm, a. c.

(No-Model.) 2 sheets-sheet 2. W. HQ ADAMS.

ROCK DRILL. No. 425,532. Patented Apr. 15, 1890;

l I /J 3 mm i S k uillkm UNITED STATES PATENT OFFICE.

WALTER II. ADAMS, OF STAMFORD, CONNECTICUT.

ROCK-DRILL.

SPECIFICATION formingpart of Letters Patent N9. 425,532, dated April 15, 1890.

Application filed May 23, 1889. Serial No. 311,804. (No model.)

To all whom it may concern:

Be it known that I, WVALTER H. ADAMS, a citizen of the United States, residing at Stamford, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Rock-Drills; and Ido hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention has reference to rock-drills, but more especially refers to the construction and operation of the valve mechanism for alternately opening and closing the ports leading, respectively, within the cylinder at opposite sides of the piston.

With these ends in view my invention consists in certain details of construction and combinations of elements, such as will be hereinafter fully set forth, and then specifically designated by the claim.

In the accompanying drawings, Figure 1 is a detail plan of the cylinder with the steamchest removed; Fig. 2, a horizontal section through the same; Fig. 3, asection at the line a; a; of Fig. l, and also showing the steamchest in position; Fig. 4,- a section at the line g y of Fig. 3; Fig. 5, a detail bottom view of the valve; and Fig. 6, a detail broken-away plan, with the steam chest and valve removed.

Similar letters denote like parts in the several figures.

A is the cylinder, and B the piston.

C is the exhaust, and D E the steam ports. Partitions a 1) separate the exhaust from the steam ports.

0 cl are sinks formed within the external surface of the cylinder adjacent to the steamports, but separated therefrom by partitions e f. These partitions a b e f form the seats for the valve, as will be presently set forth.

F is the valve-stem extending within the cylinder and capable of a free rotation therein. On the lower end of the stem is rigidly secured a rock-bar G, the ends whereof are bent upward, so as to extend within the piston-chamber H, the construction of said bar being obviously such that it cannot assume a position wherein one or both of said ends are not projected within said chamber. It will thus be readily understood that the reciprocation of the piston will cause the bar G to rock.

I is the valve secured to the upper end of the stem F and straddling the exhaust and the ports. h is a partition, which divides the valve and rendersit double. (Seen at Figs. 3 and 4.) In Fig. 4 the partition 71. is shown seated upon the seat b, and the steam will-enter from the chest J, through the sink d, within the valve, and thence through the port D, within the cylinder. I have not shown the manner of introducing the steam within the cylinder from the ports, since this is done in the ordinary manner and forms no part of my present invention. The rocking of the stem F will cause the valve to be oscillated, whereby the ports are alternately opened for the passage of the steam within the cylinder, thereby efiecting the reciprocation of the piston.

The especial feature of my invention is that the initial entrance of the'steam beneath the valve creates a balance, and the pressure required to operate the valve is one-half of what it ordinarily would be; also, my peculiarlyshaped rock-bar insures a positive movement of the valve without the use of intermediate tapp'ets, which latter become so worn by constant use as to drop away from their normal vertical position, and thereby cause an irregularity in the oscillation of the valve.

I claim The casting forming the cylinder, having a flat surface, which forms the bottom of the steam-chest J and the valve-seat and is provided with steam-ports D E, exhaust-port G, and recesses c (2, in combination with the valve I, engaging its seat in said flat surface, the valve-stem F, arranged in said casting at right angles to the line of the cylinder and secured to the valve, the rock-lever G, having its ends projecting within the cylinder and carrying the valve-stem, and thepiston arranged to strike the said ends in its reciprocation, as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

WALTER II. ADAMS. Witnesses:

F. W. GILHULEY, S. S. VVILLIAMsoN. 

